In many instances, flash illumination of a subject is used to obtain a well-exposed image. However, as flash illumination typically has a very short flash duration, it may not be possible for a camera to auto focus properly during the flash discharge event, and hence the camera is typically auto focused prior to image capture using ambient light. If, however, the ambient light spectrum used for auto focus differs from the flash light spectrum that is used for image capture, the camera focus that is obtained during auto focus may not be entirely in focus for the captured image. A need exists, therefore, for structure and methods that permit a camera to be auto focused using ambient light or some spectral subset thereof, while also providing a proper focus under a flash spectrum or some spectral subset thereof, particularly when the ambient light spectrum that is used for auto focus differs from the flash spectrum that is used for image capture.